645640325 has 48 divisors (see below), whose sum is σ = 902567232. Its totient is φ = 454080000.

The previous prime is 645640249. The next prime is 645640351. The reversal of 645640325 is 523046546.

It is a happy number.

645640325 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a de Polignac number, because none of the positive numbers 2^k-645640325 is a prime.

It is a super-2 number, since 2×645640325² = 833702858532211250, which contains 22 as substring.

It is a Smith number, since the sum of its digits (35) coincides with the sum of the digits of its prime factors.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 1950410 + ... + 1950740.

It is an arithmetic number, because the mean of its divisors is an integer number (18803484).

Almost surely, 2^645640325 is an apocalyptic number.

It is an amenable number.

645640325 is a deficient number, since it is larger than the sum of its proper divisors (256926907).

645640325 is a wasteful number, since it uses less digits than its factorization.

645640325 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 566 (or 561 counting only the distinct ones).

The product of its (nonzero) digits is 86400, while the sum is 35.

The square root of 645640325 is about 25409.4534573257. The cubic root of 645640325 is about 864.2980818237.

The spelling of 645640325 in words is "six hundred forty-five million, six hundred forty thousand, three hundred twenty-five".